A 70-year-old man died while ice bathing in the three degrees Celsius cold Baltic Sea.
The man went into the water with like-minded people from a local ice bathing club in Warnemünde on Sunday and collapsed there shortly afterwards, the police said.
A swimmer brought the man ashore and other helpers pulled him out of the water.
Despite immediate resuscitation attempts, the man died a little later on the Baltic Sea beach.
The criminal police are now determining the cause of death.
Several media had previously reported.
Icon: The mirror
bah / dpa